[ntp:questions] Peers with and without PPS Source
forensic at milwpc.com
Mon Feb 12 21:41:40 UTC 2007
I have an interesting not really problem, but mystery. I have 2 Debian Etch
machines set up with Garmin 18 GPSs and PPS (Debian1-PPS and Debian2-PPS). I
have 2 other Debian Etch machines which have no PPS source directly attached
to them (Debian3-NOPPS and Debian4-NOPPS). The Debian1-PPS and Debian2-PPS
use their own PPS source, and each other's PPS source, among other servers.
Debian3-NOPPS and Debian4-NOPPS use both the Debian1-PPS and Debian2-PPS,
among other servers. On Debian1-PPS the offset for the Debian2-PPS time is
in about 4 us, and vice versa. On the NOPPS machines, the offsets for the
PPS servers are 1-2 ms, and within us of each other.
So, it seems if a machine has a PPS source, other PPS sources used by that
machine will have much lower offsets than machines with no PPS source. Is
this a fluke? We can try to solve this mystery, hopefully for better
timekeeping for everyone.
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